Calvin Bridges

Calvin Bridges (11 January 1889-27 December 1938) was an American geneticist who discovered that sex determination in fruit flys is different than the process in humans.

Biography
Calvin Bridges was born in Schuyler Falls, New York in 1889, and he met Thomas Hunt Morgan while taking a zoology class at Columbia University. While working in Morgan's Fly Room, he discovered that the male genes in fruit flies were scattered on the non-sex chromosomes, and that the number of male genes on autosomes could balance the female X chromosome; sex determination differed in fruit flies. He died in Los Angeles in 1938.